Stackable optical ferrule and connector using same

ABSTRACT

An optical ferrule includes an optical coupling member with a light redirecting element that redirects input light from a waveguide toward an output window. The optical coupling member has a mating surface configured to slidably mate with a mating optical coupling member along a longitudinal axis of the optical ferrule. The optical ferrule also includes at least one stacking member along a longitudinal edge of the optical coupling member. The stacking member has a distal end extending beyond one of the mating surface and a top surface opposed to the mating surface. The stacking member also has a contact surface opposed to the distal end. The contact surface is configured to rotatably interface with a corresponding distal end of a of an adjacently stacked optical ferrule.

TECHNICAL FIELD

This disclosure relates generally to optical connector assemblies andmethods related to optical connector assemblies.

BACKGROUND

Optical connectors can be used for optical communications in a varietyof applications including telecommunications networks, local areanetworks, data center links, and internal links in computer devices.There is interest in extending optical communication to applicationsinside smaller consumer electronic appliances such as laptops and evencell phones. Expanded optical beams may be used in connectors for thesesystems to provide an optical connection that is less sensitive to dustand other forms of contamination and so that alignment tolerances may berelaxed. Generally, an expanded beam is a beam that is larger indiameter than the core of an associated optical waveguide (usually anoptical fiber). The connector is generally considered an expanded beamconnector if there is an expanded beam at a connection point. Theexpanded beam is typically obtained by diverging a light beam from asource or optical fiber. In many cases, the diverging beam is processedby optical elements such as a lens or mirror into an expanded beam thatis approximately collimated. The expanded beam is then received byanother waveguide after focusing of the beam via another lens or mirror.

BRIEF SUMMARY

Embodiments described herein are directed to optical ferrules, connectorassemblies using the optical ferrules, and method of making the opticalferrules. In one embodiment, an optical ferrule includes an opticalcoupling member that includes one or more light redirecting elementsconfigured to redirect input light from a waveguide attached to theoptical coupling member toward an output window of the optical couplingmember. The optical coupling member has a mating surface that includesthe output window. The mating surface is configured to slidably matewith a mating surface of a mating optical coupling member along alongitudinal axis of the optical ferrule. The optical ferrule alsoincludes at least one stacking member along a longitudinal edge of theoptical coupling member. The at least one stacking member has a distalend extending beyond one of the mating surface and a top surface opposedto the mating surface. The stacking member also has a contact surfaceopposed to the distal end. The contact surface is configured torotatably interface with a corresponding distal end of a correspondingstacking support member of an adjacently stacked optical ferrule.

In some configurations, the contact surface is further configured toslidably interface with the corresponding distal end of thecorresponding stacking support member. The at least one stacking membermay include first and second stacking members respectively located alongopposing longitudinal edges of the optical coupling member. In such anembodiment the first and second stacking members may be mirror images ofone another, and the first and second stacking members may optionallyalign the optical ferrule in a side-to-side direction with acorresponding optical coupling member of the adjacently stacked opticalferrule.

In other configurations, the contact surface may include a flat surfaceor a curved surface. The stacking member may include a triangular shape,a vertex of the triangular shape corresponding to the distal end. Thecontact surface and the corresponding distal end may include a grooveand a ridge. In such a case, the ridge fits into the groove in anunmated configuration of the optical ferrule and the adjacently stackedoptical ferrule. The ridge and the groove align the optical ferrule andthe adjacently stacked optical ferrule in a side-to-side direction.

In some configurations, the distal end extends beyond the mating surfaceand the contact surface may be recessed below the top surface of theoptical coupling member. Alternatively, the distal end may extend beyondthe mating surface and the contact surface may extend beyond the topsurface of the optical coupling member. Or, the distal end may extendbeyond the top surface and the contact surface may be recessed below themating surface of the optical coupling member.

In one configuration, the optical ferrule and the adjacently stackedoptical ferrule are part of a first connector and configured tooptically interface with respective first and second stacked matingoptical ferrules of a second connector in a mated configuration. In sucha case, the contact surface is separated from the corresponding distalend of the corresponding stacking support member in the matedconfiguration. The stacking members of the optical ferrule and theadjacently stacked optical ferrule of the first connector may includestop surfaces that contact with corresponding stop surfaces of first andsecond stacking support members of the first and second stacked opticalferrules of the first connector in the mated configuration.

In another embodiment, an optical ferrule includes an optical couplingmember having one or more light redirecting elements configured toredirect input light toward an output window of the optical couplingmember. The optical coupling member has a mating surface that includesthe output window. The mating surface configured to slidably mate with amating surface of a mating optical coupling member along a longitudinalaxis of the optical ferrule. First and second extensions are on opposedlongitudinal edges of the optical coupling member, the first and secondextensions extending beyond at least one of the mating surface and a topsurface opposed to the mating surface. A first contact surface is on thefirst extension. The first contact surface is configured to slidablyinterface with an extension of a corresponding stacking support memberof an adjacently stacked optical ferrule.

In some configurations, the optical ferrule may further include a secondcontact surface on the second extension. The second contact surface isconfigured to slidably interface with another extension of thecorresponding stacking support member. In some configurations, the firstand second extensions may be mirror images of one another, and/or thefirst contact surface may include a flat surface or a curved surface.

In some configurations, the extension may include a triangular shape. Avertex of the triangular shape slidably interfaces with a contactsurface of a second adjacently stacked optical ferrule. In otherconfigurations, the first contact surface may be recessed below a topsurface of the optical coupling member, the top surface being opposed tothe mating surface.

In some embodiments, the optical ferrule and the adjacently stackedoptical ferrule may be part of a first connector and are configured tooptically interface with respective first and second stacked matingoptical ferrules of a second connector in a mated configuration. Thefirst contact surface is separated from the corresponding distal end ofthe corresponding stacking support member in the mated configuration.The stacking support members of the optical ferrule and the adjacentlystacked optical ferrule of the first connector may include stop surfacesthat contact with corresponding stop surfaces of first and secondstacking support members of the first and second stacked opticalferrules of the first connector in the mated configuration.

In another embodiment, a connector includes a housing and at least onecolumn of one or more adjacent optical cable assemblies disposed in thehousing. Each set of optical cable subassemblies includes at least twooptical cable subassemblies. Each optical cable subassembly includes anoptical ferrule with an optical coupling member. The optical couplingmember includes one or more light redirecting elements configured toredirect input light toward an output window of the optical couplingmember. The optical coupling member also has a mating surface thatincludes the output window. The mating surface is configured to slidablymate with a mating surface of a mating optical coupling member along alongitudinal axis of the optical ferrule. The optical ferrule furtherincludes at least one extension along a longitudinal edge of the opticalcoupling member. The extension includes a distal end extending beyondthe mating surface and a contact surface opposed to the distal end. Thecontact surface is configured to rotatably interface with acorresponding distal end of a corresponding extension of an adjacentlystacked optical ferrule. Each optical cable subassembly further includesone or more optical waveguides attached to the optical ferrule. In anunmated configuration of the connector, the distal end of a firstoptical cable subassembly of the at least one column rotatablyinterfaces with the contact surface of a second optical cablesubassembly of the at least one column.

In one configuration, the distal end of the first optical cablesubassembly may slidably interface with the contact surface of thesecond optical cable subassembly. The distal end of the extension ofonly a selected one of the optical ferrules of the at least one columnmay interface with a ferrule support attached to or integral with theconnector housing. The optical ferrules of the column may be unsupportedby the housing except for the selected optical ferrule. The one or moreoptical waveguides in the cable assemblies may apply spring forces tothe respective optical ferrules. The spring forces hold the distal endof the first optical cable subassembly against the contact surface ofthe second optical cable subassembly and further hold the extension ofselected optical ferrule against the ferrule support. In a matedconfiguration, the spring forces may be applied between the matingsurfaces of the at least one column with corresponding mating surfacesof a column of mating optical cable assemblies such that the extensionof the first optical cable subassembly is separated from the contactsurface of the second optical cable subassembly and the extension of theselected optical ferrule is separated from the ferrule support.

In another embodiment, a connector includes a housing having at leastone support extending respectively from at least one of first and secondinterior walls of the housing. Two or more optical cables assemblies arestacked between the first and second interior walls. Each of the two ormore optical cable subassemblies include one or more optical waveguidesand an optical ferrule having one or more light redirecting elementsconfigured to redirect input light toward an output window of theoptical coupling member. The optical ferrule has a mating surface thatincludes the output window. The mating surface is configured to slidablymate with a mating surface of a mating optical coupling member along alongitudinal axis of the optical ferrule. An extension is located alonga longitudinal edge of the optical ferrule and extends beyond the matingsurface. A contact surface is located along the longitudinal edge. Theextension of a first of the two or more optical cable assembliesslidably interfaces with the contact surface of a second of the two ormore optical cable assemblies. The extension of the second optical cablesubassembly slidably interfaces with the at least one support of thehousing.

In some configurations, the distal end of the first optical cablesubassembly may rotatably interface with the contact surface of thesecond optical cable subassembly. The two or more optical cableassemblies are unsupported by the at least one support except for thefirst optical cable subassembly. The one or more optical waveguides mayapply spring forces to the respective optical ferrules. The springforces may hold the extension of the first optical cable subassemblyagainst the contact surface of the second optical cable subassembly andfurther hold the extension of second optical cable subassembly againstthe at least one support. In a mated configuration, the spring forcesmay be applied between the mating surfaces of the two or more opticalcable assemblies with corresponding mating surfaces of mating opticalcable assemblies such that the extension of the first optical cablesubassembly is separated from the contact surface of the second opticalcable subassembly and the extension of the selected optical ferrule isseparated from at least one support.

In another embodiment, a connector includes a housing and two or morecolumns of optical cable assemblies located side-by-side within thehousing. Each optical cable subassembly includes an optical ferrule withan optical coupling member that has one or more light redirectingelements configured to redirect input light toward an output window ofthe optical coupling member. The optical coupling member has a matingsurface that includes the output window. The mating surface isconfigured to slidably mate with a mating surface of a mating opticalcoupling member along a longitudinal axis of the optical ferrule. Theoptical ferrule includes at least one extension along a longitudinaledge of the optical coupling member. The at least one extension extendsbeyond the mating surface. The optical ferrule includes a contactsurface opposed to the at least one extension. The contact surface isconfigured to rotatably interface with a corresponding extension of anadjacently stacked optical ferrule. One or more optical waveguides areattached to the optical ferrule. The extension of a first optical cablesubassembly of each column slidably interfaces with the contact surfaceof a second optical cable subassembly of each column.

In some configurations, the extension of only a selected one opticalferrule of each column may interface with a ferrule support attached toor integral with the connector housing. The optical ferrules of the twoor more columns may be unsupported by the housing except for theselected optical ferrules of each column. For each column, the one ormore optical waveguides in the cable assemblies may apply spring forcesto the respective optical ferrules. The spring forces hold the distalend of the first optical cable subassembly against the contact surfaceof the second optical cable subassembly and further hold the extensionof selected optical ferrule against the ferrule support. In a matedconfiguration, the spring forces may be applied between the matingsurfaces of each column with corresponding mating surfaces ofcorresponding columns of mating optical cable assemblies such that, foreach column, the extension of the first optical cable subassembly isseparated from the contact surface of the second optical cablesubassembly and the extension of the selected optical ferrule isseparated from the ferrule support.

In some configurations, the housing may further include one or moreinner sidewalls separating the two or more columns of optical cableassemblies, the one or more inner sidewalls limiting side-to-sidemovement of the two or more columns within the housing. The connectormay include one or more side supports separating the two or more columnsof optical cable assemblies. The one or more side supports limitside-to-side movement within the housing of at least one optical ferrulewithin each of the two or more columns.

In another embodiment, a molded, unitary, optical ferrule includes atleast one stacking member along a longitudinal edge of the opticalferrule and one or more parting line artifacts. The one or more partingline artifacts include a parting line artifact extending substantiallyaround an external perimeter of the optical ferrule. The parting lineartifacts divide a surface of the optical ferrule into a first sectionalong a first direction of a thickness axis and an opposing secondsection along a second direction of the thickness axis. The firstsection includes a contact surface of the stacking member, one or moreelements configured to receive and secure an optical waveguide, and oneor more elements configured to redirect input light within the unitaryoptical ferrule. The second section includes at least one output windowconfigured to transmit the redirected light out of a mating surface anda distal end of the stacking member extending beyond the mating surface.The distal end is configured to interface with a corresponding contactsurface of a corresponding optical ferrule.

In some configurations, at least part of the parting artifact may extendalong an intersection between the mating surface and the longitudinaledge. The stacking member may include first and second stacking membersrespectively located along opposing longitudinal edges of the opticalcoupling member. The first and second stacking members may be mirrorimages of one another. The contact surface may include a flat surface ora curved surface. The stacking member may have a triangular shape, avertex of the triangular shape configured to interface with thecorresponding contact surface. The contact surface may be recessed belowa top surface of the optical coupling member, the top surface opposed tothe mating surface.

In another embodiment, a mold is operable to injection mold a unitary,optical ferrule. The mold has a first part configured to form: a contactsurface of a stacking member of the unitary, optical ferrule; one ormore elements of the unitary, optical ferrule configured to receive andsecure an optical waveguide; and one or more elements of the unitary,optical ferrule configured to redirect input light within the unitaryoptical ferrule. The mold includes a second part configured to form: atleast one output window of the unitary, optical ferrule configured totransmit the redirected light out of a mating surface of the unitary,optical ferrule; and a distal end of the stacking member extendingbeyond the mating surface. The distal end is configured to interfacewith a corresponding contact surface of a corresponding optical ferrule.Respective first and second surfaces of the first and second parts formone or more parting line artifacts. The one or more parting lineartifacts including a parting line artifact extending substantiallyaround an external perimeter of the unitary optical ferrule. At leastpart of the parting artifact may extend along an intersection betweenthe mating surface and the longitudinal edge.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1 and 2 are perspective views of an optical cable subassembly inaccordance with some embodiments;

FIG. 3 is a front view of a connector according to an exampleembodiment;

FIG. 4 is a side view of mating columns of optical cable subassembliesin an unmated configuration according to an example embodiment;

FIGS. 5 and 6 are side views of a connector according to an exampleembodiment;

FIG. 7 is a side view of mating columns of optical cable subassembliesin a mated configuration according to an example embodiment;

FIG. 8 is a side view of mating optical ferrules in an unmatedconfiguration according to another example embodiment;

FIG. 9 is a side view of the ferrules of FIG. 8 in a matedconfiguration;

FIG. 10 is a side view of mating optical ferrules in an unmatedconfiguration according to another example embodiment;

FIG. 11 is a side view of the ferrules of FIG. 10 in a matedconfiguration;

FIGS. 12 and 13 are front views of optical ferrules showing alignmentfeatures according to other example embodiments;

FIG. 14 is a front view of a multiple-column optical connector accordingto an example embodiment;

FIG. 15 is a front view of a multiple-column optical connector accordingto another example embodiment;

FIGS. 16 and 17 are cross-sectional views of mold parts and moldingartifacts according to an example embodiment;

FIG. 18 is a side view of a unitary, molded, optical ferrule accordingto an example embodiment;

FIGS. 19 and 20 are cross-sectional views of molds used to form ferrulesaccording to example embodiments;

FIGS. 21 and 22 are perspective views of ferrules according to anotherexample embodiment in unmated and mated configurations; and

FIGS. 23 and 24 are perspective views of ferrules according to anotherexample embodiment in unmated and mated configurations.

The figures are not necessarily to scale. Like numbers used in thefigures refer to like components. However, it will be understood thatthe use of a number to refer to a component in a given figure is notintended to limit the component in another figure labeled with the samenumber.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Embodiments described herein involve optical cable subassemblies,optical connectors and related methods. Optical cables and connectorsused in many applications may make use of one waveguide or arrays ofmultiple parallel waveguides (e.g., 4, 8 or 12 or more parallelwaveguides). The individual waveguides are typically optical fibers madeof glass with a protective buffer coating, and the parallel bufferedfibers are enclosed by a jacket. Optical connectors are useful forconnecting optical waveguides to optical waveguides, or waveguides tooptoelectronic components, for in-line interconnects and/or printedcircuit board (PCB) connections, e.g., backplane, frontplane, ormidplane connections.

One type of connector is an expanded beam connector, in which light iscoupled between waveguides in a beam that is larger in diameter than thecore of an associated optical waveguide and, in the case of waveguidearrays, typically somewhat less than the waveguide-to-waveguide pitch.The waveguides may comprise optical fibers, e.g., single-mode fibers ormulti-mode fibers for fiber optic communication systems. These expandedbeam optical connectors can have non-contact optical coupling and canprovide effective optical coupling with relaxed connector-to-connectormechanical alignment precision when compared with other types of opticalconnectors, such as physical contact connectors.

FIG. 1 shows an optical cable subassembly 100 in accordance with someembodiments. The optical cable subassembly 100 includes one or moreoptical waveguides 110 (shown here as optical fibers) and an opticalferrule 102 (also sometimes referred to as an optical coupling unit).The illustrated optical waveguide 110 includes at least one core with acladding, wherein the core and cladding are configured propagate lightwithin the core, e.g., by total internal reflection. The opticalwaveguide 110 may be, for example, a single or multi-mode waveguide, asingle core fiber, a multi-core optical fiber, or a polymeric waveguide.The waveguide may have any suitable cross-sectional shape, e.g.,circular, square, rectangular etc.

The optical ferrule 102 is configured to mate, e.g., hermaphroditically,with another optical ferrule. The optical ferrule 102 illustrated inFIG. 1 includes an optical coupling member 106 generally configured toredirect light input from the optical waveguide 110. The opticalcoupling member 106 includes a light-redirecting element 108 which maybe configured as one or more optical components (e.g., mirrors, prisms,lenses, etc.) formed within the optical coupling member 106. Thelight-redirecting element 108 redirects the light from the opticalwaveguide 110 to a mating surface 106 a of the optical coupling member106 that includes an output window (see FIG. 2). The mating surface 106a is opposed to a top surface 106 c of the optical coupling member 106.

A mechanical mating tongue 104 extends from (and may be integral to) theoptical coupling member 106. The mating tongue 104 aligns the opticalferrule 102 with a corresponding mechanical mating tongue of a matingoptical ferrule (not shown in FIG. 1). As will be described in greaterdetail below, the mating optical ferrule includes a corresponding matingsurface that facilitates mechanical and optical coupling with the matingsurface 106 a in a mated configuration of the optical ferrules. Themating surface 106 a is configured to slidably contact the correspondingmating surface along a longitudinal direction 114 of the optical ferrule102. Generally, the mating optical ferrule is longitudinally alignedwith and inverted in orientation relative to the illustrated opticalferrule 102 such that the corresponding mating surface of the matingoptical ferrule faces towards the mating surface 106 a. In someembodiments, the mating tongue 104 can have a tapering width along atleast a portion of a length of the tongue portion as shown in theillustrations. The mating tongue 104 can extend towards or outwardlyfrom a front of a connector housing (not shown in FIG. 1).

The optical coupling member 106 includes an attachment area 112 withplurality of grooves. In the illustrated embodiment, the grooves 112 awithin the attachment area 112 are aligned in the longitudinal direction114. Each groove 112 a is configured to accommodate a different one ofthe optical waveguides 110. The grooves 112 a are oriented in thelongitudinal direction 114 and configured to receive and permanentlyattach respective ones of the optical waveguides 110 to a respectivegroove at the attachment area 112, e.g., using an adhesive.

At least one stacking support member 116 is located along a longitudinaledge 106 b of the optical coupling member 106. The stacking supportmember 116 has a distal end 116 a extending beyond the mating surface106 a and a contact surface 116 b opposed to the distal end 116 a. Thecontact surface 116 b is configured to rotatably and/or slidablyinterface with a corresponding distal end of a corresponding stackingsupport member of an adjacently stacked optical ferrule (not shown inFIG. 1). The illustrated contact surface 116 b is a flat surface,although in some configurations the contact surface 116 b could beeither a convex or concave curve, and may include a combination ofcurves and flats. Generally, the adjacently stacked optical ferrule islocated vertically above the illustrated optical ferrule 102, and otheradjacently stacked optical ferrules may be vertically below theillustrated optical ferrule 102. The vertical direction is indicated byarrow 118, is normal to the mating direction of a housing that containsthe optical ferrule 102. In the latter case, the distal end 116 a of thestacking support member 116 rotatably and/or slidably interfaces with acorresponding contact surface of the adjacently stacked optical ferrule.

The stacking support member 116 is also shown with a stop surface 120that contacts a corresponding stop surface of a mating optical ferrulein the mated configuration. The stop surfaces fix the longitudinalorientation of the mated optical ferrules relative to one another. Aswill be described in further detail below, other features of the opticalferrule 102 such as the shape of the mating tongue 104 provide alignmentin other directions between the mated optical ferrules, and may be usedinstead of or in addition to the stop surface 120.

In FIG. 2, a perspective view shows additional features of the opticalcable subassembly 100 according to an example embodiment. As seen inthis view, the mating surface 106 a of the optical coupling member 106includes a window 200 which is part of an optical path within theoptical coupling member 106. Light received from the optical waveguide110 is redirected through the optical coupling member 106 where it exitsthe window 200 and enters a corresponding window of a mating opticalferrule.

Also seen in this view is a ridge 202 that is configured to interfacewith a mating tongue of a mating optical ferrule. A second ridge (notshown in this figure) mirrors the ridge 202 about a longitudinalcenterline of the optical coupling member 106. The dimensions of theridges correspond to those of the mating tongue 104 such that the matingtongue of another, mating optical ferrule is aligned together with theillustrated ferrule 102. As will be shown in detail below, the ridges202, mating tongue 104, stop surfaces 120 and mating surface 106 a allowmating optical ferrule to align respective windows 200 withoutrequiring, for example, significant longitudinal forces to be applied onthe mating optical ferrules.

As seen in the view of FIG. 2, the optical ferrule 102 includes twostacking support members 116 located along opposing longitudinal edgesof the optical coupling member 106. Note that only one of thelongitudinal edges, edge 106 b, is seen in this view. The two stackingmembers 116 (also referred to as “first and second stacking members”)are mirror images of one another, e.g., mirrored across a plane formedby axes along the longitudinal and vertical directions 114, 118, theplane bisecting the optical coupling member 106.

In FIG. 3, a front view shows a connector 300 according to an exampleembodiment. The connector 300 includes four optical cable subassemblies301-304 configured similarly to the optical cable subassembly 100 shownin FIGS. 1 and 2. Note that any number of optical subassemblies may beused. This figure uses the same convention for vertical orientation aswas used in FIGS. 1 and 2, as indicated by arrow 118. As seen in thisview, the stackable ferrules of the optical cable subassemblies 301-304result in a vertical pitch of the ferrules being equal to the verticalpitch of the optical waveguide ribbons and cable retainers (see retainer504 in FIG. 5) in the connector 300.

The optical cable subassemblies 301-304 are located between opposingwalls 312, 314 of a housing 310. The optical ferrules of thesubassemblies 301-304 are stacked one upon the other such that, in anunmated state of the connector 300, there is no intervening support(e.g., from housing 310) between adjacently stacked optical ferrules. Aclearance 323 may be provided between interior surfaces of the opposingside walls 312, 314 and the ferrules of the optical cable subassemblies301-304. This clearance 323 allows the side walls 312, 314 to restrainexcessive movement of the optical ferrules in a side-to-side direction,as indicated by arrow 322, while still allowing for some freedom ofmovement by the ferrules. Also note that the extensions of the stackingsupport members also provide side-to-side alignment between stackedoptical ferrules. For example, distal ends 306 of optical cablesubassembly 301 straddle the optical coupling member 307 of opticalcable subassembly 302. In order to support the stack of optical cablesubassemblies 301-304 within the housing 310 in the vertical direction118, ferrule supports 318, 320 extend from interior surfaces of thewalls 312, 314.

While the housing 310 may include other members besides the side walls312, 314 (e.g., top and/or bottom walls), the ferrule supports 318, 320are attached or integral with the housing 310 may be the only membersthat provide vertical support for the stack of ferrules. In thisexample, the ferrule supports 318, 320 interface with the bottomferrule's extensions. For example, extension 305 of optical cablesubassembly 304 is shown contacting ferrule support 320. In otherembodiments described herein, ferrule supports may be located andconfigured to contact other parts of the ferrules. For example, upperferrule supports, as indicated by dashed outlines 330, 332, may serve tolimit the upward motion of the ferrule stack by contacting surfaces 307and 309.

Generally, the optical waveguides of the optical cable subassemblies301-304 on both mating connectors are configured to flex within thehousing 310, causing the ferrules to be at an angle to the housing 310but parallel to each other. This angling involves rotating and slidingall of the adjacently stacked ferrules relative to one another, e.g.,during manufacture of a connector that houses the subassemblies 301-304.Because the distal end of the stacking support member (e.g., distal end306 of optical cable subassembly 301 shown in FIG. 3) is shaped torotate and/or slide against the contact surface (e.g., contact surface308 of subassembly 302) of an adjacent ferrule, the illustratedsubassemblies 301-304 can achieve this rotation without any supportmembers between adjacent ferrules. This allows the connector 300 toachieve a high density and simplifies subassembly of the connector 300.

In FIG. 4, a side view illustrates two columns 400, 420 thatrespectively include ferrules 401-404 and 421-424 of mating opticalcable subassemblies. These columns 400, 401 are part of matingconnectors that each include a housing as shown in FIG. 3, although thehousings are not shown in FIG. 4. The ferrules 401-404, 421-424 havesubstantially the same shape. Ferrules 401-404 of column 400 areinverted relative to ferrules 411-414 of column 420, such that therespective mating surfaces of a pair of mating ferrules are facing eachother. The ferrules 401-404, 411-414 are hermaphroditic, meaning theycan be made from the same mold and do not require differing features,e.g., as with male/female connectors.

Ferrule support members 410, 430 are integral with or attached to therespective housings that enclose columns 400, 401. In this figure, theferrules 401-404 and 421-424 are in an unmated configuration, shown justbefore or after being mated with one another. Mating the ferrules401-404 and 421-424 involves moving one or both of the columns inrespective directions indicated by arrows 411, 431. The arrows 411, 431are generally aligned with a longitudinal direction of the housing.Lines 412, 432 represent the longitudinal directions of the ferrules401-404, 421-424, which are generally parallel. The longitudinaldirections 412, 432 are at approximately equal acute angles 413, 433with respect to the longitudinal direction of the housing. Theorientation of the ferrules 401-404, 421-424 at the acute angles 413,433 as opposed to aligned with the longitudinal directions 411, 431 ofthe housings results in opposing forces being applied that are normal tothe mating surfaces of the ferrules 401-404, 421-424. These normalforces help ensure positive mechanical engagement between the matingsurfaces of the ferrules 401-404, 421-424, as well as other alignmentfeatures included with the ferrules 401-404, 421-424 (e.g., matingtongue 104 and ridge 202 as seen in FIG. 2). Note that the acute angles413, 433 change during mating as the ferrules rotate, resulting inbending of the fibers, and thereby increasing the normal force.

In FIG. 5, the column 400 of FIG. 4 is shown in housing 502 of opticalconnector 500. The housing 502 is shown cut away along a center-plane inthis view. Note that two ferrule support members 410 a-b are shown, onesupport member 410 a being attached to/integrated with the illustratedhalf of the housing 502 and the other support member 410 b shown“floating” to facilitate understanding of the interaction between theferrules 401-404 and the support members 410 a-B. This illustration inFIG. 5 shows optical connector subassemblies of the column before beingfinally assembled into the housing 502. A cable retainer 504 is shownattached to the optical waveguides 505-508 of the subassemblies.

As shown in FIG. 6, the cable retainer 504 is slidably inserted into thehousing, causing a bend in the optical waveguides 505-508 and causingthe ferrules 401-404 to be oriented at the acute angle 413 with respectto the housing 502. The extensions of ferrules 401-403 are pressedagainst, slide and/or rotate relative to the contact surfaces ofrespective lower adjacent stacked ferrules 402-404. The extensions offerrule 404 are pressed against, slide, and/or rotate relative to theferrule support members 410 a-b. Note that the sliding and/or rotationof adjacently stacked ferrules 401-404 against each other or against theferrule support members 410 a-b allows the ends of the ferrules to401-404 to be vertically aligned as they are angled, as indicated byvertical line 600.

The bending of the waveguides 505-508 due to sliding of the cableretainer 504 results in a force being applied to the ferrules 401-404 inan unmated configuration, causing the column of ferrules 401-404 to bepressed against the ferrule support members 410 a-b. Note that in thisconfiguration/state only the bottom ferrule 404 is directly supported bythe ferrule support members 410 a-b that are attached to or integralwith the housing 502. The other ferrules 401-403 are supported by theimmediately adjacent ferrule and not directly supported by the housing502. When the ferrules 401-404 are mated with ferrules of anotherconnector, this spring force applied by the bending of the waveguides505-508 is transferred to mating surfaces of the mating ferrules,causing the ferrules 401-404 to be lifted off of the support members 410a-b and also causing separation between extensions and contact surfacesof adjacent ferrules 401-404.

In FIG. 7, a side view shows ferrules 401-404, 421-424 in a matedconfiguration. In this configuration, the windows on the mating surfacesof the ferrules 401-404, 421-424 are facing each other and aligned suchthat light is coupled therebetween. Note that in the matedconfiguration, gaps 700 exist between respective extensions and contactsurfaces of adjacent ferrules. These gaps 700 are due to the springforces formerly being applied between ferrule extensions and ferrulecontact surfaces to be shifted such that the forces are instead appliedbetween the mating surfaces of the ferrules 401-404, 421-424, resultingin separation between extensions and contact surfaces of adjacentferrules. Similarly, gaps 702, 704 exist between support members 410,430 and respective extensions of ferrules 404, 421. The gaps 700, 702,704 in the mated configuration help ensure that the spring force appliedby the optical waveguide fibers is fully applied between the matingsurfaces of the ferrules 401-404, 421-424 and not lessened due to fullor partial contact with the support members 410, 430 or with otherferrules.

In FIGS. 8 and 9, side views show ferrules 801-804 according to anotherexample embodiment. Ferrules 801, 802 are part of a first opticalconnector and ferrules 803, 804 are part of a second optical connectorthat mates with the first optical connector. Ferrules 801, 802 includeoptical coupling member 811, 812. The optical coupling members 811, 812include light redirecting elements 811 a, 812 a configured to redirectinput light from waveguide arrays 805, 806 attached to the opticalcoupling members 811, 812. The optical coupling members 811, 812 includemating surfaces 811 b, 812 b with output windows (not shown). The matingsurfaces 811 b, 812 b are configured to slidably mate with matingsurfaces 813 b, 814 b of mating optical coupling members 813, 814 alonga longitudinal axis 807 of the optical ferrules.

Each of the optical ferrules 801, 802 includes at least one stackingmember 821, 822 along a longitudinal edge of the optical couplingmembers 811, 812. The stacking members 821, 822 include distal ends 821a, 822 a extending beyond the mating surfaces 811 b, 812 b and contactsurfaces 821 b, 822 b opposed to the distal ends 821 a, 822 a. Thecontact surface 822 b is configured to slidably and/or rotatablyinterface with corresponding distal end 821 a of a correspondingstacking support member 821 of adjacently stacked optical ferrule 801.The optical ferrules 803, 804 of the second optical connector alsoinclude similarly configured stacking members 823, 824. The stackingmembers of ferrules 801 are sufficiently large to provide a gap 900between ferrules 801 and 802 to allow ferrule 803 to mate with ferrule801 without colliding with ferrule 802.

Note that in these embodiments, the stacking members 821, 822 havecircular shape, such that the distal ends 821 a, 822 a and contactsurfaces 821 b, 822 b are respective first and second segments of therespective circles. The ferrules 801-804 are shown in an unmatedconfiguration in FIG. 8, and shown in a mated configuration in FIG. 9.Note that in the mated configuration, there is no gap in thelongitudinal direction 807 between the respective stacking members821-824. In one embodiment, contact between stacking members of matingferrules (e.g., between members 821 and 823, between 822 and 824) canserve as stops that position the optical coupling members 811-814relative to one another in the ferrule's longitudinal direction 807. Inother embodiments, the stacking members 821-824 can be positioned suchthat there is no longitudinal contact, and other features (e.g., ridges202 in FIG. 2) can be used to provide this alignment.

In FIGS. 10 and 11, side views show ferrules 1001-1004 according toanother example embodiment. The unmated configuration of ferrules1001-1004 is shown in FIG. 10 and the mated configuration is shown inFIG. 11. The ferrules 1001-1004 are configured similarly to theembodiment shown in FIGS. 8 and 9, except that the ferrules 1001-1004include elliptical stacking members 1021-1024. Thus, the contactsurfaces and extensions of the stacking members 1021-1024 are ellipticalsections. As with the previous embodiment, the major and minor axes ofthe stacking members 1021-1024 can be sized to reduce/increase stackinggap 1100 and to cause contact between the stacking members 1021-1024 ofmating ferrules 1001-1004 in the longitudinal direction 1007. In thisembodiment, the stacking members of each mated ferrule are no longer incontact with the adjacent ferrules in its stack. The separation 1025 iscaused by the rotation of the ferrules during the mating process.

In FIG. 12, a front view shows stacking members 1204, 1206 extendingfrom sides of optical ferrules 1200 1202 according to one embodiment.Distal end of stacking member 1204 includes a ridge 1208 that alignswith and fits into groove 1212 on contact surface 1215 of ferrule 1202.Distal end of stacking member 1206 includes a ridge 1210 that alignswith and fits into groove 1214 of ferrule support 1216. The ridges 1208,1210 and grooves 1212, 1214 facilitate maintaining side-to-sidealignment of the ferrules 1200, 1202 in an unmated configuration suchthat a column formed by the stacked ferrules 1200, 1202 will more easilymate with a corresponding ferrule column that uses similar alignmentfeatures. While the illustrated ridges 1208, 1210 and grooves 1212, 1214have a triangular, or V-shape, any suitable shape may be used, includingcircular, elliptical, square, etc. It is also possible that grooves andridges have different shapes, e.g., a V-shaped ridge that fits into arectangular groove. Note that the grooves and ridges may be sized suchthat the separation of stacking members from contact surfaces in themated configuration will lift the ridges 1208, 1210 out of the grooves1212, 1214. As a result, small misalignments between the ridges 1208,1210 and the grooves 1212, 1214 should not affect optical alignmentbetween mating ferrules in the mated configuration.

In FIG. 13, a front view shows stacking members 1304, 1306 extendingfrom optical ferrules 1300 1302. Distal end of stacking member 1304includes a groove 1308 that aligns with and fits around ridge 1312 oncontact surface 1315 of ferrule 1302. Distal end of stacking member 1306includes a groove 1310 that aligns with and fits around ridge 1314 offerrule support 1316. The ridges 1312, 1314 and grooves 1308, 1310operates similarly to like named components in FIG. 12, and may includedifferent shapes as described in that embodiment.

In the embodiments shown above, an optical connector includes a housingand at least one column of one or more sets of adjacent optical cableassemblies disposed in the housing. The optical cable assemblies includea ferrule according to various embodiments described above, as well asoptical waveguides (e.g., optical fiber ribbons) coupled to theferrules. This concept can be extended to multiple adjacent columns insome embodiments, as seen in the front view of FIG. 14. A housing 1400includes outer sidewalls 1400 a-b and inner sidewalls 1400 c-e. Two ormore columns 1402-1404 of optical cable assemblies are located betweenrespective sidewalls 1400 a-e. The optical cable assemblies within thecolumns 1402-1404 may be configured with ferrules and waveguidesaccording to any of the embodiments described herein.

Each of the columns 1402-1404 may be supported by a one or more ferrulesupports, as indicated by ferrule supports 1400 aa and 1400 ca thatextend respectively from sidewalls 1400 a and 1400 c. Distal ends of oneset of ferrule extensions (e.g., extensions 1402 a-b of column 1402)ride against the ferrule supports. As in previous embodiments, alternateferrule supports can be provided on the enclosure 1400 instead of or inaddition to the illustrated supports (e.g., supports 330, 332 shown inFIG. 3). Similarly, in this and other embodiments, a single ferrulesupport can span the width of one more columns such that it supports twoor more extensions from bottom ferrules. Also seen in this view are topand bottom walls 1400F-G of the enclosure 1400, which are at a non-zeroangle to (e.g., 90-degree angle) and join at least the outer sidewalls1400 a-b. As shown, the top and bottom walls 1400 f-g also join theinner sidewalls 1400 c-e.

In FIG. 15, a front view shows an arrangement of an optical connectorwith multiple adjacent columns according to another example embodiment.A housing 1500 includes outer sidewalls 1500 a-b and top and bottomwalls 1500 c-d that are at a non-zero angle to (e.g., 90-degree angle)and that join the sidewalls 1500 a-b. Two or more columns 1502-1504 ofoptical cable assemblies are located between the sidewalls 1500 a-b. Theoptical cable assemblies within the columns 1502-1504 may be configuredwith ferrules and waveguides according to any of the embodimentsdescribed herein. Each of the columns 1502-1504 may be supported by apair of ferrule supports, as indicated by ferrule support 1500 aa thatis proximate to (and may extend from) from sidewall 1500 a. Ferrulesupport 1500 da extends from the bottom wall 1500 d, and may optionallyinclude a protrusion 1500 daa that separates adjacent columns 1502,1503. Distal ends of one set of ferrule extensions (e.g., extensions1502 a-b of column 1502) ride against the ferrule supports 1500 aa, 1500da. The housing 1500 may include side supports 1500 ab, 1500 ca thatextend from the top wall 1500 c (side support 1500 ab may in addition orinstead extend from the sidewall 1500 a). These alternate side supports1500 ab, 1500 ca may ride against the optical coupling members of theferrules (e.g., against vertical surfaces that intersect contactsurfaces 1502 c-d of column 1502) to prevent excessive side-to-sidemovement of the columns 1502-1504.

Optical ferrules as described above can be formed as unitary, moldedstructures. Some embodiments described herein involve molded opticalferrules and molds for making optical ferrules. Molding ferrulesinvolves the use of two primary mold parts which are referred to hereinas the “first mold side” and the “second mold side”. The first mold sideincludes first mold features configured to mold a first set of thefeatures of the optical ferrule. The second mold side includes secondmold features configured to mold a second set of the features of theoptical ferrule. When the mold is operated, the two halves are broughttogether along what is referred to herein as the “parting axis”, thefirst side and the second side define a cavity for molding a unitaryoptical ferrule. A moldable material is injected or otherwise placedinto the cavity and hardens, e.g., due to cooling of the mold material,to form the unitary ferrule. The mold halves are then separated alongthe parting axis to allow the ferrule to be removed. Some materialsuseful for molded ferrules include thermoplastic and thermosettingpolymers, ceramics, metals, glasses, etc.

The error in alignment of the mold sides can be significant, e.g., onthe order of about 10 μm or more. In reference again to FIGS. 1 and 2,if the attachment area 112, the light-redirecting element 108, andmechanical alignment features (e.g., mating tongue 104) are not moldedby a single side of the mold, the attachment area 112 and thelight-redirecting element 108 may be misaligned with the alignmentfeatures. When such a defective ferrule is mated with a mating ferrule,the alignment features cause the optical transmission elements to beimproperly aligned with the mating ferrule, thereby increasing theoptical insertion loss of the connector. As such, the ferrule-to-ferrulealignment features (e.g., tongue 104, ridges 202, and stops 120 shownFIG. 2) can be formed on the same side of the mold with the opticalfeatures such as the light redirecting element 108 and attachment area112 to ensure accurate alignment even if the mold sides are misaligned.Because the stacking members 116 will not affect to the opticalalignment of mated ferrules, it is possible to mold them on the otherside of the mold than the optical features even if the other side of themold is misaligned.

In FIGS. 16 and 17, cross-sectional views show molds used to form aunitary ferrule according to an example embodiment. Mold 1600 in FIG. 16has first 1602 and second 1604 sides, with molded material 1606 betweenthe first and second mold sides 1602, 1604. A parting line flashartifact 1608 occurs where the molded material 170 penetrates a smallgap between the mold sides 1602, 1604. Mold 1700 in FIG. 17 has first1702 and second 1704 sides, with molded material 1706 between the firstand second mold sides 1702, 1704. A flash parting line artifact 1708occurs where the mold material 190 penetrates a small gap between themold sides 1702, 1704. A step parting line artifact 1710 occurs wherethe second side 1704 of the mold includes a vertical wall 1704 a that isslightly misaligned with the vertical wall 1702 a of the first side andthe molded material penetrates a small gap between mold sides 1702,1704.

In FIG. 18, a side view shows a molded unitary optical ferrule 1800according to an example embodiment. The ferrule 1800 includes one ormore parting line artifacts 1802. At least one of the parting lineartifacts 1802 extending substantially around an external perimeter ofthe optical ferrule 1800. The parting line artifacts 1802 divide asurface of the optical ferrule 1800 into a first section 1804 along afirst direction 1806 of a thickness axis and an opposing second section1808 along a second direction 1810 of the thickness axis.

The first section 1804 includes one or more elements 1812 configured toreceive and secure an optical waveguide, such as grooves, supports, etc.(see FIG. 1, for example). The first section 1804 also includes one ormore elements 1814 configured to redirect input light within the unitaryoptical ferrule 1800. The elements 1814 may include mirrors, lenses,internal waveguides, etc. A stacking contact surface 1816 and angledfront 1817 is also included with the first section 1804, as well as amating tongue 1825.

The second section 1808 includes at least one output window 1818configured to transmit the redirected light out of a mating surface1820. The mating surface 1820 may also be considered part of the secondsection 1808. The second section 1808 further includes at least onestacking support member 1822 along a longitudinal edge 1824 of theoptical ferrule 1800. The at least one stacking member 1822 includes anextension 1822 a having a distal end 1822 aa extending beyond the matingsurface 1820. The distal end 1822 aa is configured to rotatablyinterface with a contact surface of a corresponding stacking supportmember.

Note that in this example, the parting line artifact 1802 is located atan intersection between longitudinal sides 1824 and the mating surface1820. Also, the parting line artifact 1802 extends along an outwardfacing surface of the stacking support member 1822. In otherembodiments, parting line artifacts may extend along an edge of theextensions 1822, e.g., where two surfaces of extensions 1822 meet. Thisis shown in the following figures with illustrates example molding partsused to form the ferrule 1800.

In FIGS. 19 and 20, cross-sectional views show first and second parts1900, 1902 of a mold used to form the optical ferrule 1800 shown in FIG.18. The view of FIG. 19 corresponds to Section 19-19 through the ferrule1800 shown in FIG. 18, and illustrates details of the elements 1812configured to receive and secure optical waveguides that are formed bymold feature 1900 b. Also seen in FIG. 19 are extensions 1822 a andstacking contact surfaces 1816 on opposing longitudinal edges of theferrule, and corresponding features 1902 b, 1900 c of mold parts 1902,1900 used to form these features. Note that the intersection betweensurfaces 1900 a, 1902 a of the mold parts 1900, 1902 results in theparting line artifact 1802 shown in FIG. 18. The view of FIG. 20corresponds to Section 20-20 through the ferrule 1800 shown in FIG. 18,and illustrates details of the mating tongue 1825 and features 1900 dand 1902 c used to form the tongue 1825.

In FIGS. 21 and 22, perspective views show ferrules 2101-2104 accordingto another example embodiment. The unmated configuration of ferrules2101-2104 is shown in FIG. 21 and the mated configuration is shown inFIG. 22. The ferrules 2101-2104 include elliptical stacking members2121-2124 having distal ends 2121 a-2124 a extending beyond top surfaces2111 a-2114 a of optical coupling members 2111-2114. The top surfaces2111 a-2114 a are opposed to mating surfaces 2111 b-2114 b of theoptical coupling members 2111-2114. Contact surfaces 2121 b-2124 b ofthe stacking members 2121-2124 may be recessed below, be aligned with,or extend beyond the mating surfaces 2111 b-2114 b.

Two of the contact members 2122 b, 2123 b are shown riding againstferrule support members 2130, 2132 in the unmated configuration shown inFIG. 21. As with other embodiments, the ferrule support members 2130,2132 are attached to a connector housing or other connector support. Inthe mated configuration shown in FIG. 22, the contact members 2122 b,2123 b are lifted away from the ferrule support members 2130, 2132.Additionally in the unmated configuration, the distal ends 2122 a and2123 a are lifted off of respective adjacent contact members 2121 b,2124 b. Also note in the unmated configuration that the optical couplingmembers 2111-2114 have ridges extending from the top surfaces that (seeridges 2113 c and 2114 c in FIG. 21 extending from top surfaces 2113 a,2114 a) act as stop/alignment features in the longitudinal direction2107.

In FIGS. 23 and 24, perspective views show ferrules 2301-2304 accordingto another example embodiment. The unmated configuration of ferrules2301-2304 is shown in FIG. 23 and the mated configuration is shown inFIG. 24. The ferrules 2301-2304 include rectangular stacking members2321-2324 having distal ends 2321 a-2324 a extending beyond top surfaces2311 a-2314 a of optical coupling members 2311-2314. The top surfaces2311 a-2314 a are opposed to mating surfaces 2311 b-2314 b of theoptical coupling members 2311-2314. Contact surfaces 2321 b-2324 b ofthe stacking members 2321-2324 in this example extend beyond the matingsurfaces 2311 b-2314 b.

Two of the contact members 2322 b, 2323 b are shown riding againstferrule support members 2330, 2332 in the unmated configuration shown inFIG. 23. As with other embodiments, the ferrule support members 2330,2332 are attached to a connector housing or other connector support. Inthe mated configuration shown in FIG. 24, the contact members 2322 b,2323 b are lifted away from the ferrule support members 2330, 2332. Alsonote in this configuration that the optical coupling members 2311-2314have top surface ridges (see ridges 2323 c and 2324 c extending from topsurfaces 2313 a, 2314 a in FIG. 23) that act as stops/alignment featuresin the longitudinal direction 2307. In this example, the forces appliedby the waveguides/fibers prevent the ferrules 2301-2304 from slidingforward while stacked in the mated configuration.

It will be understood that the stacking members shown in FIGS. 21-24 mayinclude other shapes, including triangular shapes previously shown. Thestacking members may also be referred to as extensions. Reference ismade to other figures for analogous features shown in FIGS. 21-24 butnot specifically described, such as optical waveguides, elementsconfigured to redirect output light, etc.

Additional information regarding ferrules and connectors that may beused in conjunction with the approaches described herein is provided inthe following commonly owned and concurrently filed U.S. PatentApplications which are incorporated herein by reference: U.S. PatentApplication Ser. No. 62/239,998, having the title “Connector withLatching Mechanism” and identified by Attorney Docket Number 76663US002;U.S. Patent Application Ser. No. 62/240,069, having the title “OpticalFerrules” and identified by Attorney Docket Number 76982US002; U.S.Patent Application Ser. No. 62/240,066, having the title “Ferrules,Alignment Frames and Connectors,” and identified by Attorney DocketNumber 75767US002; U.S. Patent Application Ser. No. 62/240,008, havingthe title “Optical Cable Assembly with Retainer,” identified by AttorneyDocket Number 76662US002; U.S. Patent Application Ser. No. 62/240,010,having the title “Optical Coupling Device with Waveguide AssistedRegistration,” identified by Attorney Docket Number 76660US002; U.S.Patent Application 62/239,996, having the title “Optical Ferrules andOptical Ferrule Molds,” identified by Attorney Docket Number 75985US002;U.S. Patent Application 62/104,196, having the title “ConfigurableModular Connectors,” identified by Attorney Docket Number 75907US002;and U.S. Patent Application 62/240,005, having the title “HybridConnectors,” identified by Attorney Docket Number 76908US002.

Embodiments described in this disclosure include:

-   Item 1. An optical ferrule, comprising:

an optical coupling member comprising:

-   -   one or more light redirecting elements configured to redirect        input light from a waveguide attached to the optical coupling        member toward an output window of the optical coupling member;        and    -   a mating surface that includes the output window, the mating        surface configured to slidably mate with a mating surface of a        mating optical coupling member along a longitudinal axis of the        optical ferrule; and

at least one stacking member along a longitudinal edge of the opticalcoupling member, the at least one stacking member comprising:

-   -   a distal end extending beyond one of the mating surface and a        top surface opposed to the mating surface; and    -   a contact surface opposed to the distal end, the contact surface        configured to rotatably interface with a corresponding distal        end of a corresponding stacking support member of an adjacently        stacked optical ferrule.

-   Item 2. The optical ferrule of item 1, wherein the contact surface    is further configured to slidably interface with the corresponding    distal end of the corresponding stacking support member.

-   Item 3. The optical ferrule of any of items 1 and 2, where the at    least one stacking member comprises first and second stacking    members respectively located along opposing longitudinal edges of    the optical coupling member.

-   Item 4. The optical ferrule of item 3, wherein the first and second    stacking members are mirror images of one another.

-   Item 5. The optical ferrule of item 3, wherein the first and second    stacking members align the optical ferrule in a side-to-side    direction with a corresponding optical coupling member of the    adjacently stacked optical ferrule.

-   Item 6. The optical ferrule of any of items 1-5, wherein the contact    surface comprises a flat surface.

-   Item 7. The optical ferrule of any of item 1-5, wherein the contact    surface comprises a curved surface.

-   Item 8. The optical ferrule of any of items 1-7, wherein the    stacking member comprises a triangular shape, a vertex of the    triangular shape corresponding to the distal end.

-   Item 9. The optical ferrule of any of items 1-8, wherein the contact    surface and the corresponding distal end comprise a groove and a    ridge, the ridge fitting into the groove in an unmated configuration    of the optical ferrule and the adjacently stacked optical ferrule,    the ridge and the groove aligning the optical ferrule and the    adjacently stacked optical ferrule in a side-to-side direction.

-   Item 10. The optical ferrule of any of items 1-9, wherein the distal    end extends beyond the mating surface and the contact surface is    recessed below the top surface of the optical coupling member.

-   Item 11. The optical ferrule of any of items 1-9, wherein the distal    end extends beyond the mating surface and the contact surface    extends beyond the top surface of the optical coupling member.

-   Item 12. The optical ferrule of any of items 1-9, wherein the distal    end extends beyond the top surface and the contact surface is    recessed below the mating surface of the optical coupling member.

-   Item 13. The optical ferrule of any of items 1-12, wherein the    optical ferrule and the adjacently stacked optical ferrule are part    of a first connector and configured to optically interface with    respective first and second stacked mating optical ferrules of a    second connector in a mated configuration, wherein the contact    surface is separated from the corresponding distal end of the    corresponding stacking support member in the mated configuration.

-   Item 14. The optical ferrule of any of items 1-13, wherein the    stacking members of the optical ferrule and the adjacently stacked    optical ferrule of the first connector comprise stop surfaces that    contact with corresponding stop surfaces of first and second    stacking support members of the first and second stacked optical    ferrules of the first connector in the mated configuration.

-   Item 15. An optical ferrule, comprising:

an optical coupling member comprising:

-   -   one or more light redirecting elements configured to redirect        input light toward an output window of the optical coupling        member; and    -   a mating surface that includes the output window, the mating        surface configured to slidably mate with a mating surface of a        mating optical coupling member along a longitudinal axis of the        optical ferrule;

first and second extensions on opposed longitudinal edges of the opticalcoupling member, the first and second extensions extending beyond atleast one of the mating surface and a top surface opposed to the matingsurface; and

a first contact surface on the first extension, the first contactsurface configured to slidably interface with an extension of acorresponding stacking support member of an adjacently stacked opticalferrule.

-   Item 16. The optical ferrule of item 15, further comprising a second    contact surface on the second extension, the second contact surface    configured to slidably interface with another extension of the    corresponding stacking support member.-   Item 17. The optical ferrule of any of items 15 and 16, wherein the    first and second extensions are mirror images of one another.-   Item 18. The optical ferrule of any of items 15-17, wherein the    first contact surface comprises a flat surface.-   Item 19. The optical ferrule of any of items 15-17, wherein the    first contact surface comprises a curved surface.-   Item 20. The optical ferrule of any of items 15-19, wherein the    extension comprises a triangular shape, a vertex of the triangular    shape slidably interfacing with a contact surface of a second    adjacently stacked optical ferrule.-   Item 21. The optical ferrule of any of items 15-20, wherein the    first contact surface is recessed below a top surface of the optical    coupling member, the top surface being opposed to the mating    surface.-   Item 22. The optical ferrule of any of items 15-21, wherein the    optical ferrule and the adjacently stacked optical ferrule are part    of a first connector and configured to optically interface with    respective first and second stacked mating optical ferrules of a    second connector in a mated configuration, wherein the first contact    surface is separated from the corresponding distal end of the    corresponding stacking support member in the mated configuration.-   Item 23. The optical ferrule of item 22, wherein the stacking    support members of the optical ferrule and the adjacently stacked    optical ferrule of the first connector comprise stop surfaces that    contact with corresponding stop surfaces of first and second    stacking support members of the first and second stacked optical    ferrules of the first connector in the mated configuration.-   Item 24. A connector comprising:

a housing; and

at least one column of one or more adjacent optical cable assembliesdisposed in the housing, each set of optical cable subassembliescomprising at least two optical cable subassemblies, each optical cablesubassembly comprising:

-   -   an optical ferrule comprising:        -   an optical coupling member comprising:            -   one or more light redirecting elements configured to                redirect input light toward an output window of the                optical coupling member; and            -   a mating surface that includes the output window, the                mating surface configured to slidably mate with a mating                surface of a mating optical coupling member along a                longitudinal axis of the optical ferrule; and        -   at least one extension along a longitudinal edge of the            optical coupling member, the extension comprising:            -   a distal end extending beyond the mating surface; and            -   a contact surface opposed to the distal end, the contact                surface configured to rotatably interface with a                corresponding distal end of a corresponding extension of                an adjacently stacked optical ferrule; and    -   one or more optical waveguides attached to the optical ferrule,

wherein, in an unmated configuration of the connector, the distal end ofa first optical cable subassembly of the at least one column rotatablyinterfaces with the contact surface of a second optical cablesubassembly of the at least one column.

-   Item 25. The connector of item 24, wherein the distal end of the    first optical cable subassembly slidably interfaces with the contact    surface of the second optical cable subassembly.-   Item 26. The connector of any of items 24 and 25, wherein the distal    end of the extension of only a selected one of the optical ferrules    of the at least one column interfaces with a ferrule support    attached to or integral with the connector housing.-   Item 27. The connector of item 26, wherein the optical ferrules of    the column are unsupported by the housing except for the selected    optical ferrule.-   Item 28. The connector of item 27, wherein the one or more optical    waveguides in the cable assemblies apply spring forces to the    respective optical ferrules, the spring forces holding the distal    end of the first optical cable subassembly against the contact    surface of the second optical cable subassembly and further hold the    extension of selected optical ferrule against the ferrule support.-   Item 29. The connector of item 28, wherein, in a mated    configuration, the spring forces are applied between the mating    surfaces of the at least one column with corresponding mating    surfaces of a column of mating optical cable assemblies such that    the extension of the first optical cable subassembly is separated    from the contact surface of the second optical cable subassembly and    the extension of the selected optical ferrule is separated from the    ferrule support.-   Item 30. A connector comprising:

a housing comprising at least one support extending respectively from atleast one of first and second interior walls of the housing;

two or more optical cables assemblies stacked between the first andsecond interior walls, each comprising:

-   -   one or more optical waveguides;    -   an optical ferrule comprising one or more light redirecting        elements configured to redirect input light toward an output        window of the optical coupling member and a mating surface that        includes the output window, the mating surface configured to        slidably mate with a mating surface of a mating optical coupling        member along a longitudinal axis of the optical ferrule;    -   an extension along a longitudinal edge of the optical ferrule,        the extension extending beyond the mating surface; and    -   a contact surface along the longitudinal edge; and    -   wherein the extension of a first of the two or more optical        cable assemblies slidably interfaces with the contact surface of        a second of the two or more optical cable assemblies, and        wherein the extension of the second optical cable subassembly        slidably interfaces with the at least one support of the        housing.

-   Item 31. The connector of item 30, wherein the distal end of the    first optical cable subassembly rotatably interfaces with the    contact surface of the second optical cable subassembly.

-   Item 32. The connector of any of items 30-31, wherein the two or    more optical cable assemblies are unsupported by the at least one    support except for the first optical cable subassembly.

-   Item 33. The connector of item 32, wherein the one or more optical    waveguides apply spring forces to the respective optical ferrules,    the spring forces holding the extension of the first optical cable    subassembly against the contact surface of the second optical cable    subassembly and further hold the extension of second optical cable    subassembly against the at least one support.

-   Item 34. The connector of item 33, wherein, in a mated    configuration, the spring forces are applied between the mating    surfaces of the two or more optical cable assemblies with    corresponding mating surfaces of mating optical cable assemblies    such that the extension of the first optical cable subassembly is    separated from the contact surface of the second optical cable    subassembly and the extension of the selected optical ferrule is    separated from at least one support.

-   Item 35. A connector comprising:

a housing;

two or more columns of optical cable assemblies located side-by-sidewithin the housing, each optical cable subassembly comprising:

-   -   an optical ferrule comprising:        -   an optical coupling member comprising:            -   one or more light redirecting elements configured to                redirect input light toward an output window of the                optical coupling member; and            -   a mating surface that includes the output window, the                mating surface configured to slidably mate with a mating                surface of a mating optical coupling member along a                longitudinal axis of the optical ferrule; and        -   at least one extension along a longitudinal edge of the            optical coupling member, the at least one extension            extending beyond the mating surface; and        -   a contact surface opposed to the at least one extension, the            contact surface configured to rotatably interface with a            corresponding extension of a an adjacently stacked optical            ferrule; and    -   one or more optical waveguides attached to the optical ferrule,        wherein the extension of a first optical cable subassembly of        each column slidably interfaces with the contact surface of a        second optical cable subassembly of each column.

-   Item 36. The connector of item 35, wherein the extension of only a    selected one optical ferrule of each column interfaces with a    ferrule support attached to or integral with the connector housing.

-   Item 37. The connector of item 36, wherein the optical ferrules of    the two or more columns are unsupported by the housing except for    the selected optical ferrules of each column.

-   Item 38. The connector of item 37, wherein, for each column, the one    or more optical waveguides in the cable assemblies apply spring    forces to the respective optical ferrules, the spring forces holding    the extension of the first optical cable subassembly against the    contact surface of the second optical cable subassembly and further    hold the extension of selected optical ferrule against the ferrule    support.

-   Item 39. The connector of item 38, wherein, in a mated    configuration, the spring forces are applied between the mating    surfaces of each column with corresponding mating surfaces of    corresponding columns of mating optical cable assemblies such that,    for each column, the extension of the first optical cable    subassembly is separated from the contact surface of the second    optical cable subassembly and the extension of the selected optical    ferrule is separated from the ferrule support.

-   Item 40. The connector of any of items 35-39, wherein the housing    further comprises one or more inner sidewalls separating the two or    more columns of optical cable assemblies, the one or more inner    sidewalls limiting side-to-side movement of the two or more columns    within the housing.

-   Item 41. The connector of item any of items 35-40, further    comprising one or more side supports separating the two or more    columns of optical cable assemblies, the one or more side supports    limiting side-to-side movement within the housing of at least one    optical ferrule within each of the two or more columns.

-   Item 42. A molded, unitary, optical ferrule comprising:

at least one stacking member along a longitudinal edge of the opticalferrule;

one or more parting line artifacts, the one or more parting lineartifacts including a parting line artifact extending substantiallyaround an external perimeter of the optical ferrule, the parting lineartifacts dividing a surface of the optical ferrule into a first sectionalong a first direction of a thickness axis and an opposing secondsection along a second direction of the thickness axis, wherein thefirst section comprises:

-   -   a contact surface of the stacking member;    -   one or more elements configured to receive and secure an optical        waveguide; and    -   one or more elements configured to redirect input light within        the unitary optical ferrule; and

wherein the second section comprises

-   -   at least one output window configured to transmit the redirected        light out of a mating surface; and

a distal end of the stacking member extending beyond the mating surface,the distal end configured to interface with a corresponding contactsurface of a corresponding optical ferrule.

-   Item 43. The molded, unitary, optical ferrule of item 42, wherein at    least part of the parting artifact extends along an intersection    between the mating surface and the longitudinal edge.-   Item 44. The molded, unitary, optical ferrule of any of items 42-43,    wherein the stacking member comprises two stacking members    respectively located along opposing longitudinal edges of the    optical coupling member.-   Item 45. The molded, unitary, optical ferrule of item 44, wherein    the first and second stacking members are mirror images of one    another.-   Item 46. The molded, unitary, optical ferrule of any of items 42-45,    wherein the contact surface comprises a flat surface.-   Item 47. The molded, unitary, optical ferrule of any of items 42-45,    wherein the contact surface comprises a curved surface.-   Item 48. The molded, unitary, optical ferrule of any of items 42-47,    wherein the stacking member comprises a triangular shape, a vertex    of the triangular shape configured to interface with the    corresponding contact surface.-   Item 49. The molded, unitary, optical ferrule of any of items 42-48,    wherein the contact surface is recessed below a top surface of the    optical coupling member, the top surface opposed to the mating    surface.-   Item 50. A mold operable to injection mold a unitary, optical    ferrule, the mold comprising:

a first part configured to form:

-   -   a contact surface of a stacking member of the unitary, optical        ferrule;    -   one or more elements of the unitary, optical ferrule configured        to receive and secure an optical waveguide; and    -   one or more elements of the unitary, optical ferrule configured        to redirect input light within the unitary optical ferrule; and

a second part configured to form:

-   -   at least one output window of the unitary, optical ferrule        configured to transmit the redirected light out of a mating        surface of the unitary, optical ferrule; and    -   an extension of the stacking member comprising a distal end        extending beyond the mating surface, the distal end configured        to interface with a corresponding contact surface of a        corresponding optical ferrule;    -   wherein respective first and second surfaces of the first and        second parts form one or more parting line artifacts, the one or        more parting line artifacts including a parting line artifact        extending substantially around an external perimeter of the        unitary optical ferrule.

-   Item 51. The mold of claim 50, wherein at least part of the parting    artifact extends along an intersection between the mating surface    and the longitudinal edge.

Unless otherwise indicated, all numbers expressing feature sizes,amounts, and physical properties used in the specification and claimsare to be understood as being modified in all instances by the term“about.” Accordingly, unless indicated to the contrary, the numericalparameters set forth in the foregoing specification and attached claimsare approximations that can vary depending upon the desired propertiessought to be obtained by those skilled in the art utilizing theteachings disclosed herein. The use of numerical ranges by endpointsincludes all numbers within that range (e.g. 1 to 5 includes 1, 1.5, 2,2.75, 3, 3.80, 4, and 5) and any range within that range.

Various modifications and alterations of the embodiments discussed abovewill be apparent to those skilled in the art, and it should beunderstood that this disclosure is not limited to the illustrativeembodiments set forth herein. The reader should assume that features ofone disclosed embodiment can also be applied to all other disclosedembodiments unless otherwise indicated. It should also be understoodthat all U.S. patents, patent applications, patent applicationpublications, and other patent and non-patent documents referred toherein are incorporated by reference, to the extent they do notcontradict the foregoing disclosure.

1-10. (canceled)
 11. An optical ferrule, comprising: an optical couplingmember comprising: one or more light redirecting elements configured toredirect input light from a waveguide attached to the optical couplingmember toward an output window of the optical coupling member; and amating surface that includes the output window, the mating surfaceconfigured to slidably mate with a mating surface of a mating opticalcoupling member along a longitudinal axis of the optical ferrule; and atleast one stacking member along a longitudinal edge of the opticalcoupling member, the at least one stacking member comprising: a distalend extending beyond one of the mating surface and a top surface opposedto the mating surface; and a contact surface opposed to the distal end,the contact surface configured to rotatably interface with acorresponding distal end of a corresponding stacking support member ofan adjacently stacked optical ferrule.
 12. The optical ferrule of claim11, wherein the contact surface is further configured to slidablyinterface with the corresponding distal end of the correspondingstacking support member.
 13. The optical ferrule of claim 11, whereinthe at least one stacking member comprises first and second stackingmembers respectively located along opposing longitudinal edges of theoptical coupling member, and wherein the first and second stackingmembers align the optical ferrule in a side-to-side direction with acorresponding optical coupling member of the adjacently stacked opticalferrule.
 14. The optical ferrule of claim 11, wherein the at least onestacking member comprises first and second stacking members respectivelylocated along opposing longitudinal edges of the optical couplingmember, the first and second stacking members being mirror images of oneanother.
 15. The optical ferrule of claim 11, wherein the stackingmember comprises a triangular shape, a vertex of the triangular shapecorresponding to the distal end.
 16. The optical ferrule of claim 11,wherein the contact surface and the corresponding distal end comprise agroove and a ridge, the ridge fitting into the groove in an unmatedconfiguration of the optical ferrule and the adjacently stacked opticalferrule, the ridge and the groove aligning the optical ferrule and theadjacently stacked optical ferrule in a side-to-side direction.
 17. Theoptical ferrule of claim 11, wherein the optical ferrule and theadjacently stacked optical ferrule are part of a first connector andconfigured to optically interface with respective first and secondstacked mating optical ferrules of a second connector in a matedconfiguration, wherein the contact surface is separated from thecorresponding distal end of the corresponding stacking support member inthe mated configuration, and wherein the stacking members of the opticalferrule and the adjacently stacked optical ferrule of the firstconnector comprise stop surfaces that contact with corresponding stopsurfaces of first and second stacking support members of the first andsecond stacked optical ferrules of the first connector in the matedconfiguration.
 18. An optical ferrule, comprising: an optical couplingmember comprising: one or more light redirecting elements configured toredirect input light toward an output window of the optical couplingmember; and a mating surface that includes the output window, the matingsurface configured to slidably mate with a mating surface of a matingoptical coupling member along a longitudinal axis of the opticalferrule; first and second extensions on opposed longitudinal edges ofthe optical coupling member, the first and second extensions extendingbeyond at least one of the mating surface and a top surface opposed tothe mating surface; and a first contact surface on the first extension,the first contact surface configured to slidably interface with anextension of a corresponding stacking support member of an adjacentlystacked optical ferrule.
 19. The optical ferrule of claim 18, furthercomprising a second contact surface on the second extension, the secondcontact surface configured to slidably interface with another extensionof the corresponding stacking support member.
 20. The optical ferrule ofclaim 18, wherein the extension comprises a triangular shape, a vertexof the triangular shape slidably interfacing with a contact surface of asecond adjacently stacked optical ferrule.
 21. The optical ferrule ofclaim 18, wherein the optical ferrule and the adjacently stacked opticalferrule are part of a first connector and configured to opticallyinterface with respective first and second stacked mating opticalferrules of a second connector in a mated configuration, wherein thefirst contact surface is separated from the corresponding distal end ofthe corresponding stacking support member in the mated configuration.22. The optical ferrule of claim 21, wherein the stacking supportmembers of the optical ferrule and the adjacently stacked opticalferrule of the first connector comprise stop surfaces that contact withcorresponding stop surfaces of first and second stacking support membersof the first and second stacked optical ferrules of the first connectorin the mated configuration.
 23. A connector comprising: a housing; andat least one column of one or more adjacent optical cable assembliesdisposed in the housing, each set of optical cable subassembliescomprising at least two optical cable subassemblies, each optical cablesubassembly comprising: an optical ferrule comprising: an opticalcoupling member comprising: one or more light redirecting elementsconfigured to redirect input light toward an output window of theoptical coupling member; and a mating surface that includes the outputwindow, the mating surface configured to slidably mate with a matingsurface of a mating optical coupling member along a longitudinal axis ofthe optical ferrule; and at least one extension along a longitudinaledge of the optical coupling member, the extension comprising: a distalend extending beyond the mating surface; and a contact surface opposedto the distal end, the contact surface configured to rotatably interfacewith a corresponding distal end of a corresponding extension of anadjacently stacked optical ferrule; and one or more optical waveguidesattached to the optical ferrule, wherein, in an unmated configuration ofthe connector, the distal end of a first optical cable subassembly ofthe at least one column rotatably interfaces with the contact surface ofa second optical cable subassembly of the at least one column.
 24. Theconnector of claim 23, wherein the distal end of the extension of only aselected one of the optical ferrules of the at least one columninterfaces with a ferrule support attached to or integral with theconnector housing, wherein the optical ferrules of the column areunsupported by the housing except for the selected optical ferrule, andwherein the one or more optical waveguides in the cable assemblies applyspring forces to the respective optical ferrules, the spring forcesholding the distal end of the first optical cable subassembly againstthe contact surface of the second optical cable subassembly and furtherhold the extension of selected optical ferrule against the ferrulesupport.
 25. The connector of claim 24, wherein, in a matedconfiguration, the spring forces are applied between the mating surfacesof the at least one column with corresponding mating surfaces of acolumn of mating optical cable assemblies such that the extension of thefirst optical cable subassembly is separated from the contact surface ofthe second optical cable subassembly and the extension of the selectedoptical ferrule is separated from the ferrule support.
 26. A connectorcomprising: a housing comprising at least one support extendingrespectively from at least one of first and second interior walls of thehousing; two or more optical cables assemblies stacked between the firstand second interior walls, each comprising: one or more opticalwaveguides; an optical ferrule comprising one or more light redirectingelements configured to redirect input light toward an output window ofthe optical coupling member and a mating surface that includes theoutput window, the mating surface configured to slidably mate with amating surface of a mating optical coupling member along a longitudinalaxis of the optical ferrule; an extension along a longitudinal edge ofthe optical ferrule, the extension extending beyond the mating surface;and a contact surface along the longitudinal edge; and wherein theextension of a first of the two or more optical cable assembliesslidably interfaces with the contact surface of a second of the two ormore optical cable assemblies, and wherein the extension of the secondoptical cable subassembly slidably interfaces with the at least onesupport of the housing.
 27. The connector of claim 26, wherein thedistal end of the first optical cable subassembly rotatably interfaceswith the contact surface of the second optical cable subassembly.
 28. Aconnector comprising: a housing; two or more columns of optical cableassemblies located side-by-side within the housing, each optical cablesubassembly comprising: an optical ferrule comprising: an opticalcoupling member comprising: one or more light redirecting elementsconfigured to redirect input light toward an output window of theoptical coupling member; and a mating surface that includes the outputwindow, the mating surface configured to slidably mate with a matingsurface of a mating optical coupling member along a longitudinal axis ofthe optical ferrule; and at least one extension along a longitudinaledge of the optical coupling member, the at least one extensionextending beyond the mating surface; and a contact surface opposed tothe at least one extension, the contact surface configured to rotatablyinterface with a corresponding extension of a an adjacently stackedoptical ferrule; and one or more optical waveguides attached to theoptical ferrule, wherein the extension of a first optical cablesubassembly of each column slidably interfaces with the contact surfaceof a second optical cable subassembly of each column.
 29. The connectorof claim 28, wherein the housing further comprises one or more innersidewalls separating the two or more columns of optical cableassemblies, the one or more inner sidewalls limiting side-to-sidemovement of the two or more columns within the housing.
 30. Theconnector of claim 28, further comprising one or more side supportsseparating the two or more columns of optical cable assemblies, the oneor more side supports limiting side-to-side movement within the housingof at least one optical ferrule within each of the two or more columns.